Melvenor

Glad it works not only for me :]

Yo, man. Had the same problem. Googled this issue and found your thread... then googled further and found the solution. ;) We get it because we both installed DLCs AFTER the update (updates all ArmA's and DLCs through Steam). And DLC installers are outdated I think, got both BAF and PMC from BIS Store though (both 1.00 versions I think, that's why we get errors). So all you need is to download and run this update. It applies that ArmA 2 and OA are already updated to the latest version and will patch BAF and PMC to the latest versions. I did it and play w/o any errors etc. Cheers! P.S. Ah, yes. In the future there won't any need to manually download updates. Steam will detect DLCs and will update them too.